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The information in this proxy statement is not complete and may be changed. This proxy statement is not an offer to sell these securities, and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

Preliminary — Subject to Completion Dated March 5, 2015

102 South Clinton St.

Iowa City, Iowa 52240

(319) 356-5800

March [·], 2015

Dear Shareholder:

MidWestOne Financial Group, Inc., an Iowa corporation, has entered into an Agreement and Plan of Merger pursuant to which Central Bancshares, Inc. will merge with and into MidWestOne Financial Group, Inc., with MidWestOne Financial Group, Inc. remaining as the surviving corporation (the “Merger”).  The consideration for the Merger includes $64.0 million of cash and 2,723,083 shares of our common stock, which represent approximately 32.5% of our outstanding shares of common stock prior to the issuance of such shares, based on our outstanding shares of common stock at February 27, 2015.

We cordially invite you to attend the special meeting of shareholders of MidWestOne Financial Group, Inc. to be held at 10:00 a.m. (Central Time) on April 23, 2015, at the Company’s headquarters located at 102 South Clinton Street, Iowa City, Iowa, at which our shareholders will consider a proposal to approve the Merger, pursuant to the Agreement and Plan of Merger, dated November 20, 2014, between MidWestOne Financial Group, Inc., and Central Bancshares, Inc., and issuance of shares of our common stock in connection therewith.  Our shares of common stock are listed on The NASDAQ Global Select Market under the symbol “MOFG.”  Therefore, pursuant to Iowa law and Rule 5635(a) of The NASDAQ Stock Market LLC, the issuance of more than 20% of our outstanding common stock requires approval by a majority of the total votes cast on the proposal at a meeting of shareholders at which a quorum is present.  Our shareholders will also be asked to approve a proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies to approve the issuance of shares of our common stock. We encourage you to carefully read the accompanying Notice of Special Meeting of Shareholders and proxy statement, which discuss the business to be conducted at the meeting in greater detail.

We recommend that you vote your shares “FOR” the Merger and issuance of shares of our common stock in connection therewith and “FOR” any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies.

This is a special meeting and is not our regular annual shareholders’ meeting, which has been postponed until the summer as a result of the pending Merger.  You are welcome to attend the special meeting although there will not be a reception or financial presentation, which will take place at the annual shareholders’ meeting.  Whether or not you plan to attend the meeting in person, please take the time to vote by completing and mailing the enclosed proxy card or by following the telephone or Internet voting procedures described on the proxy card. This will assure that your shares are represented at the meeting.

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102 South Clinton St.

Iowa City, Iowa 52240

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS

TO BE HELD APRIL 23, 2015

To Our Shareholders:

The special meeting of the shareholders of MidWestOne Financial Group, Inc. will be held at 10:00 a.m. (Central Time) on April 23, 2015, at the Company’s headquarters located at 102 South Clinton Street, Iowa City, Iowa, for the following purposes:

1.              to approve the merger of Central Bancshares, Inc. with and into MidWestOne Financial Group, Inc., with MidWestOne Financial Group, Inc., remaining as the surviving corporation (the “Merger”) pursuant to the Agreement and Plan of Merger, dated November 20, 2014, between MidWestOne Financial Group, Inc., and Central Bancshares, Inc. (the “Merger Agreement”) and issuance of 2,723,083 shares of our common stock, subject to certain adjustments, in connection therewith;

2.              to approve any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies in order to approve the Merger and issuance of shares of our common stock; and

3.              to transact such other business as may properly be brought before the special meeting, or any adjournments or postponements of the special meeting, including whether or not to adjourn the special meeting.

Under Iowa law, we are required to obtain shareholder approval of the Merger and issuance of shares of our common stock in connection therewith. In addition, because our common stock is listed on The NASDAQ Global Select Market, Rule 5635(a) of The NASDAQ Stock Market LLC requires that the issuance of shares of our common stock in connection with the Merger receive the approval of our shareholders.  Therefore, the proposal regarding the Merger and the issuance of shares of our common stock in connection therewith must be approved by a majority of the total votes cast on the proposal.

In the event that it is necessary to postpone or adjourn the special meeting, for, among other reasons, the solicitation of additional votes to approve the proposal regarding the Merger and issuance of shares of our common stock in connection therewith, we also have submitted the question of adjournment to the shareholders as a separate matter for their consideration. The adjournment proposal must be approved by the affirmative vote of a majority of the votes cast on the proposal at the meeting.

Your board of directors unanimously recommends that you vote “FOR” the Merger and issuance of shares of our common stock in connection therewith and “FOR” any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies.

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Only shareholders of record on our books at the close of business on February 27, 2015, the record date for the special meeting, are entitled to notice of, and to vote at, the special meeting and any adjournments or postponements of the special meeting. In the event there are an insufficient number of votes for a quorum, the meeting may be adjourned or postponed in order to permit us to further solicit proxies.

Important Notice Regarding the Availability of Proxy Materials
for the Shareholder Meeting to Be Held on April 23, 2015.

Our proxy statement for the special meeting of shareholders to be held on April 23, 2015 and other proxy materials are available at http://ir.midwestone.com/docs.aspx?iid=1021746.

Iowa City, Iowa
March [·], 2015

WHETHER OR NOT YOU PLAN TO ATTEND THE SPECIAL MEETING IN PERSON, PLEASE TAKE THE TIME TO VOTE BY COMPLETING AND MAILING THE ENCLOSED PROXY CARD OR BY FOLLOWING THE TELEPHONE OR INTERNET VOTING PROCEDURES DESCRIBED ON THE PROXY CARD.  IF YOU DO ATTEND THE MEETING, YOU MAY VOTE YOUR SHARES IN PERSON IF YOU WISH. YOU MAY REVOKE THE PROXY CARD AT ANY TIME PRIOR TO ITS EXERCISE.

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APPENDICES:

APPENDIX A:             Agreement and Plan of Merger, dated November 20, 2014, between MidWestOne Financial and Central Bancshares, Inc.

APPENDIX B:             Fairness Opinion of Sandler O’Neill & Partners, L.P.

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MIDWESTONE FINANCIAL GROUP, INC.

PROXY STATEMENT

SPECIAL MEETING OF SHAREHOLDERS

APRIL 23, 2015

This proxy statement and the accompanying proxy card are being furnished to our shareholders in connection with the solicitation by our board of directors of proxies to be used at the special meeting of shareholders to be held at 10:00 a.m. (Central Time) on April 23, 2015, at the Company’s headquarters located at 102 South Clinton Street, Iowa City, Iowa, or at any adjournments or postponements of the meeting. This proxy statement is first being mailed to our shareholders on or about March [·], 2015.

QUESTIONS AND ANSWERS

The following is information regarding the merger, the meeting and the voting process, presented in a question and answer format. As used in this proxy statement, the terms “MidWestOne Financial,” “the Company,” “we,” “our,” and “us” all refer to MidWestOne Financial Group, Inc. and its consolidated subsidiaries. The term “MidWestOne Bank” and “the Bank” refer to the Company’s wholly-owned banking subsidiary, MidWestOne Bank, Iowa City, Iowa.  The term “Central” refers to Central Bancshares, Inc., a Minnesota corporation.  The term “Merger Agreement” refers to the Agreement and Plan of Merger, dated November 20, 2014, between the Company and Central, as may be amended. The term “Merger” refers to the merger of Central with and into the Company pursuant to the terms of the Merger Agreement.  The term “Shareholder Agreement” refers to the Shareholder Agreement, dated November 20, 2014, by and among the Company, the John M. Morrison Revocable Trust #4 (the “Shareholder”), CBSI LLC (f/k/a CBS LLC) (the “TruPS Holder”), the holder of all outstanding preferred securities of CBI Capital Trust III (the “TruPS”), Riverbank Insurance Center, Inc., the holder of all outstanding Class A units (the “Insurance Agency Units”) of Central Insurance Agency, LLC (the “Insurance Agency Owner”) and John M. Morrison, an individual with common control over the Shareholder, the TruPS Holder and the Insurance Agency Owner (“Mr. Morrison”).

Q:                                  What is a proxy?

A:                                   A proxy is a document, also referred to as a “proxy card,” on which you authorize someone else to vote for you in the way that you want to vote. You may also choose to abstain from voting. The proxy is being solicited by our board of directors.

Q:                                  What is a proxy statement?

A:                                   A proxy statement is a document, such as this one, required by the Securities and Exchange Commission (the “SEC”) that, among other things, explains the items on which you are asked to vote on the proxy card.

Q:                                  Why am I receiving this proxy statement and the accompanying proxy card?

A:                                   You are receiving this proxy statement and the accompanying proxy card from us because on February 27, 2015, the record date for the special meeting, you owned shares of MidWestOne Financial common stock. This proxy statement describes the matters that will be presented for consideration by our shareholders at the special meeting to be held on April 23, 2015. It also gives you information concerning the matters to assist you in making an informed decision.

When you sign the enclosed proxy card or otherwise vote pursuant to the instructions set forth in the proxy card, you appoint the proxy holders as your representatives at the meeting. The proxy holders will vote your shares as you have instructed, thereby ensuring that your shares will be voted whether or not you attend the meeting. Even if you plan to attend the meeting, we ask that you instruct the proxies how to vote your shares in advance of the meeting just in case your plans change and you are unable to attend in person.

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If you have signed and returned the proxy card and an issue comes up for a vote at the meeting that is not identified on the card, the proxy holders will vote your shares, pursuant to your proxy, in accordance with their judgment.

Q:                                  What matters will be voted on at the meeting?

A:                                   You are being asked to vote on: (i) the Merger and issuance of 2,723,083 shares of our common stock, as may be adjusted, in connection therewith pursuant to the terms of the Merger Agreement; and (ii) any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies in order to approve the issuance of shares of our common stock. These matters are more fully described in this proxy statement.

Q:                                  What is the Merger?

A:                                   The Company and Central have entered into the Merger Agreement, pursuant to which Central will merge with and into the Company, with the holders of Central common stock receiving, in the aggregate, 2,723,083 shares of the Company’s common stock and $64.0 million in cash, subject to certain possible adjustments, as described further under “The Merger—Merger Consideration,” in exchange for their shares of Central common stock (the “Merger Consideration”).

The Shareholder owned all of the shares of Central’s common stock on the date of the Merger Agreement and as of this proxy statement.  The Merger was approved by the Shareholder by written consent on November 20, 2014. The Merger cannot be completed on the terms described in the Merger Agreement unless, among other things, the shareholders of the Company approve the Merger and issuance of our common stock in connection therewith.

Q:                                  What is the purpose of this vote?

A:                                   Our shareholders are being asked to approve the Merger and issuance of our common stock in connection therewith pursuant to Iowa law. In addition, because the Company’s common stock is listed on The NASDAQ Global Select Market, Rule 5635(a) of The NASDAQ Stock Market LLC requires that our shareholders approve any proposed issuance of common stock in connection with the acquisition of another company if: (i) the common stock to be issued has, or will have upon issuance, voting power equal to or in excess of 20% of the voting power outstanding before the issuance of the stock; or (ii) the number of shares of common stock to be issued is or will be equal to or in excess of 20% of the number of shares of common stock outstanding before the issuance of the stock or securities. The number of shares to be issued in connection with the Merger represents approximately 32.5% of our outstanding shares of common stock prior to the issuance of such shares, based on our outstanding shares of common stock at February 27, 2015. As a result, our shareholders must approve the issuance of shares of our common stock in connection with the Merger pursuant to the Rules governing our listing on The NASDAQ Global Select Market as well as Iowa law.

In addition, our shareholders are being asked to approve any adjournment of the special meeting, if necessary or appropriate, to allow time for further solicitation of proxies in the event there are insufficient votes present at the special meeting, in person or by proxy, to approve the issuance of shares of our common stock.

Q:                                  Why do the Company and Central want to merge?

A:                                   The Company and Central believe that the proposed Merger will create a strong, independent financial services institution, headquartered in Iowa with operations in Iowa, Minnesota, Wisconsin and southwest Florida, with greater resources and the potential to achieve greater earnings and balance sheet growth than each of the organizations on a standalone basis. The Company and Central believe their customers will appreciate the expanded geographic presence of the Company following the Merger, and their shareholders will benefit from owning stock in a company with greater capital and resources. The Merger is expected to create a platform for expanding the Company’s branch network and, if opportunities arise, possible future strategic transactions and acquisition opportunities.

Q:                                  What will shareholders receive in the Merger?

A:                                   Central shareholders: The shares of Central’s common stock will be exchanged for 2,723,083 shares of the Company’s common stock and $64.0 million in cash, subject to certain possible adjustments, as described further under “The Merger—Merger Consideration.” Each outstanding share of the Company’s common stock will remain outstanding after the Merger. The Company currently plans to finance the cash portion of the merger consideration through the combination of a dividend from the Bank and a loan from a third-party

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correspondent lender.  It is estimated that holders of Central’s common stock will own approximately 24.5% of the outstanding common stock of the Company following the Merger.  As of the date of this proxy statement, the Shareholder owned all of Central’s common stock.

Company shareholders: Our shareholders will not receive any Merger Consideration if the Merger is completed but will continue to hold the shares of the Company’s common stock that they currently hold. The Company will issue common stock and cash as Merger Consideration to the holders of Central common stock as set forth above and our current shareholders will be diluted. It is estimated that the current holders of the Company’s common stock will own approximately 75.5% of the outstanding common stock of the Company following the Merger.

Q:                                  Will the value of the Merger Consideration change between now and the time of completion of the Merger?

A:                                   Although the number of shares of the Company’s common stock that the Company will issue in the Merger is fixed, the value of the Merger Consideration will fluctuate based upon the market price of the Company’s common stock. As of November 19, 2014, the value of the Merger Consideration to be paid by the Company was approximately $135.1 million, based on the closing price of $26.10 per share of Company common stock on that date. The value of the Merger Consideration to be paid by the Company will fluctuate to the extent that the price of the Company’s common stock exceeds or is less than $26.10 per share at closing. The Merger Agreement also provides, however, that Central may terminate the Merger Agreement if the price of the Company’s common stock decreases below a certain amount, but in such instance, the Company will have the option to increase the cash portion of the Merger Consideration to prevent such a termination, as described further under “The Merger—Merger Consideration.”

Q:                                  When do you expect to complete the Merger?

A:                                   We are working to complete the Merger in the second quarter of 2015. However, the closing of the Merger is contingent on a number of closing conditions, and we cannot guarantee when or if all of these conditions will be met.

Q:                                  How many votes may I cast?

A:                                   Generally, you are entitled to cast one vote for each share of stock you owned on the record date. The proxy card included with this proxy statement indicates the number of shares owned by an account attributable to you as of the record date.

Q:                                  How many votes are needed for each proposal?

A:                                   A majority of the votes cast on the proposals at the meeting will approve each matter that arises at the special meeting.  The Merger and issuance of shares of our common stock in connection therewith and the adjournment of the special meeting are both considered to be non-routine matters. As a result, if your shares are held by a broker or other fiduciary, it cannot vote your shares on these matters unless it has received voting instructions from you.

Abstentions and broker non-votes, if any, will not be counted as votes cast, but will count for purposes of determining whether or not a quorum is present. Accordingly, so long as a quorum is present, abstentions and broker non-votes will have no effect on any of the matters presented for a vote at the special meeting.

Q:                                  How do I vote?

A:                                   After reviewing this document, submit your proxy using any of the proxy delivery or voting methods indicated on the proxy card. By submitting your proxy, you authorize the individuals named in it to represent you and vote your shares at the special meeting in accordance with your instructions. Your vote is important. Whether or not you plan to attend the special meeting, please submit your proxy card promptly in the enclosed envelope or vote telephonically or through the Internet by following the instructions on the proxy card.

If you sign and return your proxy card but do not mark the card to provide voting instructions, the shares represented by your proxy card will be voted “for” the Merger and issuance of shares of our common stock in connection therewith and “for” any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies.

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If you are a beneficial owner and a broker or other fiduciary is the record holder (which is usually referred to as “street name” ownership), then you received this proxy statement from the record holder of the shares that you beneficially own. The record holder should have given you instructions for directing how the record holder should vote your shares. It will then be the record holder’s responsibility to vote your shares for you in the manner you direct.

If you want to vote in person, please come to the meeting. We will distribute written ballots to anyone who wants to vote at the meeting. Please note, however, that if your shares are held in the name of a broker or other fiduciary (i.e., in street name), you will need to arrange to obtain a legal proxy from the record holder in order to vote in person at the meeting. Even if you plan to attend the special meeting, we ask that you complete and return your proxy card in advance of the special meeting in case your plans change.

Q:                                  If I hold shares in the name of a broker, who votes my shares?

A:                                   Under the rules of various national and regional securities exchanges, brokers and other fiduciaries that hold securities on behalf of beneficial owners generally may vote on routine matters even if they have not received voting instructions from the beneficial owners for whom they hold securities, but are not permitted to vote on non-routine matters unless they have received such voting instructions. The Merger and issuance of shares of our common stock in connection therewith and the adjournment of the special meeting are considered to be non-routine matters. Thus, if you do not provide instructions to your broker as to how it should vote the shares beneficially owned by you, your broker generally will not be permitted to vote on the matters described in this proxy statement.

We therefore encourage you to provide directions to your broker as to how you want your shares voted on all matters to be brought before the meeting. You should do this by carefully following the instructions your broker gives you concerning its procedures.

Q:                                  How will my shares of common stock held in the employee stock ownership plan be voted?

A:                                   We maintain an employee stock ownership plan (“ESOP”) that owns 295,314 or 3.5% of the current outstanding shares of our common stock. Employees of the Company and the Bank participate in the ESOP.  As of the record date, 274,057 shares have been allocated to ESOP participants. Each ESOP participant has the right to instruct the trustee of the plan how to vote the shares of our common stock allocated to his or her account under the ESOP. If an ESOP participant properly executes the voting instruction card, the ESOP trustee will vote the participant’s shares in accordance with the participant’s instructions. Shares of our common stock held in the ESOP, but not allocated to any participant’s account, and allocated shares for which no voting instructions are received from participants, will be voted by the trustee in proportion to the results of the votes cast on the issue by the participants and beneficiaries.

Q:                                  What does it mean if I receive more than one proxy card?

A:                                   It means that you have multiple holdings reflected in our stock transfer records and/or in accounts with stockbrokers. Please sign and return ALL proxy cards to ensure that all of your shares are voted.

Q:                                  What if I change my mind after I return my proxy card?

A:                                   If you hold your shares in your own name, you may revoke your proxy and change your vote at any time before the polls close at the meeting. You may do this by:

·                  signing another proxy card with a later date and returning that proxy card to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, New York 11717, by mail;

·                  timely submitting another proxy via the telephone or Internet, if that is the method that you originally used to submit your proxy;

·                  sending notice to us that you are revoking your proxy; or

·                  voting in person at the meeting.

All written notices of revocation and other written communications with respect to revocation of proxies should be sent to: MidWestOne Financial Group, Inc., 102 South Clinton St., Iowa City, Iowa 52240,

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Attention: Corporate Secretary. If you hold your shares in the name of your broker or other fiduciary and desire to change your voting instructions, you will need to contact that party directly.

Q:                                  How many votes do we need to hold the special meeting?

A:                                   A majority of the shares that are outstanding and entitled to vote as of the record date must be present in person or by proxy at the meeting in order to hold the meeting and conduct business. Shares are counted as present at the meeting if the shareholder either:

·                  is present and votes in person at the meeting; or

·                  has properly submitted a signed proxy card or other form of proxy (through the telephone or Internet).

On February 27, 2015, the record date, there were 8,370,309 shares of common stock issued and outstanding. Therefore, at least 4,185,155 shares need to be present, in person or by proxy, at the special meeting.

Q:                                  What options do I have in voting on each of the proposals?

A:                                   You may vote “for,” “against” or “abstain” on each proposal properly brought before the meeting.

Q:                                  How does the board recommend that I vote?

A:                                   The board of directors of the Company approved the Merger Agreement, determined that the issuance of shares of our common stock in connection with the Merger is in the best interests of the Company’s shareholders, and unanimously recommends that Company shareholders vote “FOR” the Merger and issuance of shares of our common stock in connection therewith and “FOR” any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies.

Q:                                  How will my shares be voted if I return a blank proxy card?

A:                                   If you sign and date your proxy card but do not indicate how you want to vote, your proxies will be counted as a vote “FOR” the Merger and issuance of shares or our common stock in connection therewith and “FOR” any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies, and in the discretion of the persons named as proxies on any other matters properly presented at the special meeting.

Q:                                  Where do I find the voting results of the meeting?

A:                                   If available, we will announce voting results at the meeting. The voting results also will be disclosed in a Form 8-K that we expect to file within four business days after the meeting.

Q:                                  Do I have the right to dissent and obtain the “fair value” for my shares?

A:                                   No. None of Iowa corporate law, our articles of incorporation or our bylaws provide our shareholders with the right to dissent with respect to the Merger or the issuance of shares of our common stock in connection with the Merger.

Q:                                  Are there any restrictions on the shares being issued?

A:                                   Yes. The shares of our common stock issued in the Merger will be issued under an exemption from registration under the Securities Act of 1933, as amended (the “Securities Act”). The shares will therefore be restricted securities and may not be sold absent registration under the Securities Act or pursuant to Rule 144 under the Securities Act or another available exemption from registration.  Additionally, the Shareholder and certain of its affiliated entities are parties to the Shareholder Agreement, which generally prohibits the sale of our common stock for a period of one year following the consummation of the Merger.

Q:                                  What are the material U.S. federal income tax consequences of the Merger to Company shareholders?

A:                                   The Merger, the issuance of shares of our common stock, and the other transactions associated with the Merger are not expected to have any tax effect on our current shareholders for U.S. federal income tax purposes.

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The U.S. federal income tax consequences of the Merger described above and elsewhere in the proxy statement may not apply to all shareholders and will depend on each shareholder’s specific factual situation. Accordingly, we strongly urge you to consult your own independent tax advisor for a full understanding of the particular tax consequences of the Merger to you.

Q:                                  Who bears the cost of soliciting proxies?

A:                                   We will bear the cost of soliciting proxies. In addition to solicitations by mail, our officers, directors or employees may solicit proxies in person or by telephone. These persons will not receive any special or additional compensation for soliciting proxies. We may reimburse brokerage houses and other custodians, nominees and fiduciaries for their reasonable out-of-pocket expenses for forwarding proxy and solicitation materials to shareholders.

Q:                                  Who can answer my questions?

A:                                   You should contact the Company’s Corporate Secretary at 102 South Clinton Street, P.O. Box 1700, Iowa City, Iowa 52244-1700, via telephone at (319) 356-5800 or via email at webmaster@midwestone.com.

YOUR VOTE IS IMPORTANT. PLEASE RETURN YOUR MARKED AND SIGNED PROXY CARD PROMPTLY SO YOUR SHARES CAN BE REPRESENTED, EVEN IF YOU PLAN TO ATTEND THE MEETING IN PERSON.

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SUMMARY

This summary highlights selected information contained elsewhere in this document. This summary may not contain all of the information important to you. We urge you to read this entire document carefully, including the exhibits and appendices, to make sure that you understand the Merger fully. See “Where You Can Find More Information” included elsewhere in this document. Each item in this summary contains a reference to the page in this document where such item is discussed in further detail.

The Companies (page 27 for the Company and page 27 for Central)

MidWestOne Financial Group, Inc.

MidWestOne Financial Group, Inc. is a $1.8 billion holding company headquartered in Iowa City, Iowa. The Company provides financial services to individuals, businesses, governmental units and institutional customers in central and east-central Iowa through its wholly owned subsidiaries, MidWestOne Bank and MidWestOne Insurance Services, Inc. As of February 28, 2015, the Bank operated in central and east-central Iowa through 25 full service banking locations. The Bank is actively engaged in many areas of commercial banking, including: acceptance of demand, savings and time deposits; making commercial, real estate, agricultural and consumer loans; and other banking services tailored for its individual customers.  As of December 31, 2014, the Company, on a consolidated basis, had assets of approximately $1.8 billion, deposits of approximately $1.4 billion, and shareholders’ equity of approximately $192 million.

The Company’s executive offices are located at 102 South Clinton Street, Iowa City, Iowa 52240, its telephone number is (319) 356-5800, and its website is maintained at www.midwestone.com. The Company’s common stock is traded on The NASDAQ Global Select Market under the symbol “MOFG.”

Central Bancshares, Inc.

Central Bancshares, Inc. is a $1.18 billion holding company headquartered in Golden Valley, Minnesota. Central provides commercial and retail loan and deposit services principally to customers within the Minneapolis-St. Paul metropolitan area of Minnesota, western Wisconsin and southwest Florida through its wholly owned subsidiary, Central Bank.  As of February 28, 2015, Central Bank operated in Minnesota through 13 banking locations, in Wisconsin through 7 banking locations and in Florida through 2 banking locations. The southwest area of Florida makes up approximately four percent of Central’s consolidated assets and operations. As of December 31, 2014, Central, on a consolidated basis, had assets of approximately $1.18 billion, deposits of approximately $1.06 billion, and shareholders’ equity of approximately $80.4 million.

Central’s executive offices are located at 945 Winnetka Avenue North, Suite 145, Golden Valley, Minnesota 55427, its telephone number is (763) 512-5299, and its website is maintained at www.centralbnk.com.

Special Meeting of Shareholders (page 28)

The Company will hold its special meeting of shareholders on April 23, 2015, at 10:00 a.m. (Central Time) at the Company’s headquarters located at 102 South Clinton Street, Iowa City, Iowa, to vote on: (i) the Merger and issuance of 2,723,083 shares of our common stock in connection with the Merger; and (ii) any adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies in order to approve the issuance of shares of our common stock.

Record Date (page 28)

If you owned shares of our common stock at the close of business on February 27, 2015, the record date for the special meeting, you are entitled to vote on the issuance of shares of our common stock in connection with the Merger, the adjournment of the special meeting, as well as any other matters considered at the special meeting. On the record date, there were 8,370,309 shares of our common stock outstanding. You will have one vote at the meeting for each share of common stock you owned on the record date

Voting (page 28)

A majority of the votes cast at the meeting is required to approve each of (i) the Merger and issuance of shares of our common stock in connection therewith; and (ii) the adjournment of the special meeting. As of February 11, 2015, our directors and executive officers and their affiliates beneficially owned approximately 7.1% of the outstanding shares of our common stock.

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Appraisal Rights (see page 29)

Neither the Merger nor the issuance of shares of our common stock in connection with the Merger creates a right to dissent or otherwise seek appraisal rights for our shareholders.

The Merger (page 30)

Under the terms of the Merger Agreement, Central will merge with and into the Company, with the Company being the surviving corporation. Following the Merger, each of the Bank and Central Bank will continue in existence as wholly owned subsidiaries of the Company. The Merger Agreement is attached as Appendix A and is incorporated into this proxy statement by reference. We encourage you to read the Merger Agreement carefully as it is the legal document that governs the Merger.

Merger Consideration (page 30)

If and when the Merger is consummated, each outstanding share of Central common stock will be exchanged for a pro rata portion of 2,723,083 shares of the Company’s common stock and $64.0 million in cash, subject to certain possible adjustments.  The Company currently plans to finance the cash portion of the Merger Consideration through the combination of a dividend from the Bank and a loan from a third party correspondent lender.

Effective Time of the Merger (see page 30)

The Merger is currently expected to close in the second quarter of 2015. However, the closing of the Merger is conditioned on the satisfaction of certain conditions to closing contained in the Merger Agreement. Neither the Company nor Central can predict the actual date on which the Merger will be completed because the closing is subject to factors beyond each company’s control.

Our Reasons for the Merger and Board Recommendation (see page 32)

The Company and Central believe that the proposed Merger will create a strong, independent financial services institution, headquartered in Iowa with operations in Iowa, Minnesota, Wisconsin and southwest Florida, with greater resources and the potential to achieve greater earnings and balance sheet growth than each of the organizations on a standalone basis. You can find a more detailed discussion of the background of the Merger and our reasons for the Merger in this proxy statement under “The Merger—Background of the Merger” and “The Merger—Our Reasons for the Merger and Board Recommendation.” The discussion of our reasons for the Merger includes forward-looking statements about possible or assumed future results of our operations and the performance of the Company after the Merger. For a discussion of factors that could affect these future results, see “Cautionary Note Regarding Forward-Looking Statements.”

Our board of directors has determined that the issuance of shares of our common stock in connection the Merger, the Merger Agreement and the transactions contemplated by the Merger Agreement are advisable and in the best interests of the Company and our shareholders and has approved the Merger Agreement. Our board of directors unanimously recommends that our shareholders vote “FOR” the approval of the Merger and issuance of shares or our common stock in connection therewith.

Fairness Opinion of Sandler O’Neill & Partners, L.P., the Company’s Financial Advisor (page 33)

Sandler O’Neill & Partners, L.P. (“Sandler O’Neill”) has delivered a written opinion, dated November 20, 2014, to the Company’s board of directors that the Merger Consideration to be paid in the Merger is fair to the Company from a financial point of view. We have attached this opinion to this document as Appendix B. You should read this opinion carefully to understand the procedures followed, matters considered and limitations on the reviews undertaken by Sandler O’Neill in providing its opinion.

Regulatory Approvals (page 39)

The Merger Agreement provides that closing of the Merger is conditioned on the receipt of all required regulatory approvals, including the approval of the Board of Governors of the Federal Reserve System (the “Federal Reserve”) and the Minnesota Department of Commerce.

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Management and Operations after the Merger (page 39)

The present management groups of both companies will share the responsibility of managing the Company after the completion of the Merger. The executive management team of the Company following the Merger will include officers of both the Company and Central. The board of directors of the Company following the Merger will initially be comprised of thirteen members, eight designated by the Company and five designated by Central.

Interests of Certain Persons in the Merger (page 42)

Each of the directors and executive officers of the Company owns shares of our common stock, as further detailed under “Security Ownership of Certain Beneficial Owners and Management.”  Certain directors and officers of the Company will also have positions with the Company after the Merger, and certain directors and officers of Central have entered into employment agreements and/or change in control agreements with the Company.  Additionally, certain directors and officers of the Company will receive the benefit of the Shareholder Agreement.  See “The Merger Agreement — Shareholder Agreement.”  The Company will provide indemnification and directors’ and officers’ liability insurance for the Company’s directors and officers.

NASDAQ Listing (page 44)

The Company will list the shares of its common stock to be issued in connection with the Merger on The NASDAQ Global Select Market under the symbol “MOFG.”

Restrictions on the Resale of the Shares of Our Common Stock (page 45)

The shares of our common stock issued in the Merger will be issued under an exemption from registration under the Securities Act. The shares will therefore be restricted securities and may not be sold absent registration under the Securities Act or pursuant to Rule 144 under the Securities Act or another available exemption from registration. Additionally, the sole shareholder of Central and certain of its affiliated entities are parties to the Shareholder Agreement, which generally prohibits the sale of our common stock for a period of one year following the consummation of the Merger.  The Shareholder Agreement also grants to the sole Shareholder of Central certain registration rights and permits the sales of common stock issued in the Merger pursuant to such registrations beginning 180 days after the closing of the Merger.

Conditions to Completion of the Merger (page 45)

The completion of the Merger depends on a number of conditions being met. Subject to exceptions described in the Merger Agreement, these include:

·                  the receipt of the required approvals from our shareholders;

·                  the receipt of all necessary consents and approvals;

·                  the accuracy of the respective representations and warranties of the Company and Central in the Merger Agreement;

·                  compliance in all material respects by each of the Company and Central with their respective covenants and agreements in the Merger Agreement;

·                  the absence of any event that has had or would be reasonably likely to have a material adverse effect on the other party;

·                  the receipt from McGladrey LLP (“McGladrey”) of a tax opinion that the Merger qualifies as a tax-free reorganization under Section 368(a) of the Internal Revenue Code of 1986, as amended (the “Code”);

·                  the absence of any proceeding, statute, rule, regulation, injunction or other order prohibiting the consummation of performance of the transactions contemplated by the Merger Agreement;

·                  the approval for listing on The NASDAQ Global Select Market of the shares of our common stock to be issued in the Merger;

·                  compliance by Central’s shareholders and affiliates subject to the Shareholder Agreement with the covenants and obligations in the Shareholder Agreement;

·                  the amount of Central’s adjusted shareholder’s equity not being less than $70 million; and

·                  the receipt of financing to fund the Merger Consideration.

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Termination of the Merger Agreement (page 49)

The parties can mutually agree at any time to terminate the Merger Agreement without completing the Merger. Also, either party can decide, without the consent of the other, to terminate the Merger Agreement if the Merger has not been completed by June 30, 2015, unless the failure to complete the Merger by that time is due to a violation of the Merger Agreement by the party seeking to terminate the Merger Agreement.

In addition, either the Company or Central can terminate the Merger Agreement if the conditions to its respective obligation to complete the Merger have not been satisfied, other than through the failure of that party to comply with its obligations under the Merger Agreement or the Shareholder Agreement.

Additionally, the Company can terminate the Merger Agreement if certain issues with respect to the titles or surveys of Central’s real property are discovered and Central fails to correct such issues, and either the Company or Central can terminate the Merger Agreement if environmental issues relating to Central’s real property are discovered and the costs to remediate such issues exceed $1,000,000.

Either the Company or Central can also terminate the Merger Agreement if any regulatory agency required to approve the proposed transactions has issued a final, non-appealable order denying the proposed transactions, or any application, filing or notice for regulatory approval has been withdrawn at the request or recommendation of the applicable regulatory agency.

The Merger Agreement also provides that Central may terminate the Merger Agreement if the price of the Company’s common stock decreases below a certain amount, but, in such instance, the Company will have the option of increasing the cash portion of the Merger Consideration to prevent such a termination.

Shareholder Agreement (page 50)

Concurrently with the execution of the Merger Agreement, the Company, the Shareholder, the TruPS Holder, the Insurance Agency Owner and Mr. Morrison entered into the Shareholder Agreement.  The Shareholder Agreement contains many important agreements between the parties thereto with respect to the Merger, certain special rights and obligations relating to the shares of common stock of the Company issued in conjunction with the Merger and certain other transactions between the parties. The Shareholder Agreement is attached as Exhibit G to the Merger Agreement found in Appendix A and is incorporated into this proxy statement by reference.  We encourage you to read the Shareholder Agreement carefully for a complete understanding of its terms and provisions and the obligations of the Company, the Shareholder, the TruPS holder, the Insurance Agency Owner and Mr. Morrison thereunder.

Certain Material U.S. Federal Income Tax Consequences (page 51)

The Merger, the issuance of shares of our common stock in connection with the Merger, and the other transactions associated with the Merger are not expected to have any tax effect on our current shareholders for U.S. federal income tax purposes.

The parties intend for the Merger to qualify as a “reorganization” within the meaning of Section 368(a) of the Code. It is a condition to the Company and Central’s obligation to complete the Merger that they receive an opinion from McGladrey, dated the closing date of the Merger, to the effect that the Merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Code.

See “Material U.S. Federal Income Tax Consequences of the Merger” for a more detailed discussion of the tax consequences of the Merger.

The U.S. federal income tax consequences described above may not apply to all holders of the Company’s common stock. Your tax consequences will depend on your individual situation. Accordingly, we strongly urge you to consult your independent tax advisor for a full understanding of the particular tax consequences of the Merger and the related transactions to you.

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MARKET PRICE AND DIVIDEND INFORMATION

Our common stock is traded on The NASDAQ Global Select Market under the symbol “MOFG.” The following table sets forth the reported high and low sales prices of shares of our common stock, and the quarterly cash dividends per share declared, in each case for the periods indicated.  The high and low sales prices are based on intraday sales for the periods reported.

On November 20, 2014, the last full trading day before the public announcement of the Merger Agreement, the high and low sales prices of shares of our common stock as reported on The NASDAQ Global Select Market were $25.98 and $25.32, respectively. On March 4, 2015, the last practicable trading day before the date of this proxy statement, the high and low sales prices of shares of our common stock as reported on The NASDAQ Global Select Market were $28.51 and $28.02, respectively.

As of March 4, 2015, the last date prior to printing this proxy statement for which it was practicable to obtain this information, there were approximately 480 registered holders of our common stock and approximately 1,938 beneficial holders and one registered holder of Central common stock.

Each of our shareholders is advised to obtain current market quotations for our common stock. The market price of our common stock will fluctuate between the date of this proxy statement and the date of completion of the Merger. No assurance can be given concerning the market price of our common stock before or after the effective date of the Merger. Changes in the market price of our common stock prior to the completion of the Merger will affect the market value of the stock portion of the Merger Consideration that Central shareholders will receive upon completion of the Merger.

Historical market price information regarding Central is not provided because there is no public market for Central’s common stock. Central has elected to be taxed as a Subchapter S corporation and, therefore, the Shareholder is responsible to pay any tax liabilities of Central.  Central has historically paid dividends to the Shareholder to, in part, allow the Shareholder to pay the tax liability associated with Central’s earnings.  Central paid a dividend of $1.8 million between January 1, 2015, and the date of this proxy statement and expects to pay another dividend of $10.0 million to the Shareholder between the date of this proxy statement and the date of the Merger.  Dividends of $9.6 million were paid in 2014, $9.6 million were paid in 2013 and $9.0 million were paid in 2012. Pursuant to the terms of the Merger Agreement, Central may declare and pay tax dividends equal to forty percent of Central’s net income earned between January 31, 2015 and the effective time of the Merger.

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SELECTED HISTORICAL FINANCIAL DATA OF THE COMPANY

The following table presents selected consolidated historical financial data for the periods and at the dates indicated for the Company. You should read the following table in conjunction with the consolidated financial statements and notes thereto included in reports that the Company has previously filed with the SEC.

Historical results do not necessarily indicate the results that you can expect for any future period. Management believes that all adjustments (which include only normal recurring adjustments) necessary to arrive at a fair presentation of the Company’s interim results of operations have been included.

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*                                   All financial ratios have been calculated under the regulatory capital rules in effect on December 31, 2014, and do not factor in the rules implemented by Basel III.

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SUPPLEMENTARY FINANCIAL INFORMATION OF THE COMPANY

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SELECTED HISTORICAL FINANCIAL DATA OF CENTRAL

The following table presents selected consolidated historical financial data for the periods and at the dates indicated for Central. You should read the following table in conjunction with the consolidated financial statements and notes thereto included in this proxy statement beginning on page F-1.

Historical results do not necessarily indicate the results that you can expect for any future period. Management believes that all adjustments (which include only normal recurring adjustments) necessary to arrive at a fair presentation of Central’s interim results of operations have been included.

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